Also note, how both creating a record and updating properties on the record through the levelUp method requires
us to wrap these operations into a run function. You can read more the Ember run loop over here.

Testing Relationships

For relationships you probably only want to test that the relationship
declarations are setup properly.

Assume that a User can own a Profile.

You can follow along by generating your own user and profile models with ember
generate model user and ember generate model profile.

Ember Data contains extensive tests around the functionality of
relationships, so you probably don't need to duplicate those tests. You could
look at the Ember Data tests for examples of deeper relationship testing if you
feel the need to do it.